Judson learned that having the high horsepower peak was not going to win this contest. "This was harder than anything we've done," says Judson. Having the 2,500- and 6,500-rpm torque figures equally weighted made it necessary to have consistently high numbers through that 4,000-rpm range. This was an uncharted goal previous to this challenge.
The 2007 SAM team consisted of two students, one instructor, and Judson. The students, both of whom currently work at Judson's school, were chosen for their talent and work ethic. They, along with other students, confronted the task of engine choice and came up with some good options. Ford heads had a preferred design, but with the abundance of Chevrolet fans in his school, he knew one Bow Tie motor would have to be thrown into the mix this year. He started out with three engines: a 351 Cleveland, a 400 modified Ford, and a 400 Chevrolet. The 400M, with its experimental custom rod combination, showed winning numbers, but unfortunately these rods were a weak link, and the remaining parts were transplanted to the 351C. The Ford, as it always seems to, showed impressive numbers. Focus was shifted to the 400 Chevrolet.
The build started with a Chevrolet Bow Tie block outfitted with Precision Product's bronze lifter bushings. From the factory, production blocks can be up to 5 degrees out of specification. In a '92 Chevy Tahoe, this may not be an issue, but in the world of high-performance engines, it needs to be checked. The installation of these bushings called for an overbore and alignment to get within tolerance. Judson explains: "These bushings serve to correct the alignment of the lifter bores without changing the diameter. Rules require that the lifter bore diameter remain unchanged from Chevrolet's factory .843 inch."
The 400M showed its weakness with the connecting rods, and Judson was not going to let that happen again. The 400 was outfitted with a Lunati crank that needed only a standard balance. Unlike a factory crankshaft, this Lunati piece was set up as an internal balance so it wouldn't need a counterweighted flywheel/flexplate or harmonic balancer. Lunati 6.125-inch rods and Wiseco pistons were bolted together with ARP fasteners. Around these pistons, Judson used a Total Seal Diamond Finish ring set. The second ring, a Napier ring, has a step, causing it to act like a squeegee removing oil from the cylinder wall. To insure constant oiling, he used a Melling 10553 race pump and a Stef's oil pan designed for a '66 Chevy II. He planned to use 0W20-weight oil. This oil was changed to 5W30 Royal Purple after Judson saw the environment in which the engine would be tested, and figured it prudent to add higher viscosity. He suggested that if this engine would be used on the street, he would move that up to 10W40. Judson, like many builders, sees free horsepower in low-pressure, low-volume pumps. "The less oil you have flying around there, the better," he states.